Normal methanol plant start-up requires nine hours to fourteen hours to heat the hydrodesulphurization section to an optimum temperature to activate the dehydrosulfurization catalyst before feeding natural gas to the saturator for further processing. Since natural gas is being used for heating and is also concurrently being vented to flare, the existing start up process wastes substantial amounts of natural gas which has negative impact on the environment and also reduces the overall efficiency of the plant.
Accordingly, what is needed is a process which efficiently recycles natural gas instead of venting the natural gas to the flare system. Recycling of natural gas until the hydrodesulphurization section reaches the required temperature increases overall plant efficiency, enhances production, saves significant amounts of natural gas and reduces the carbon footprint of the plant.